I'm actually surprised this hasn't been done before.  I know I can use filters but as a DM I'm frequently looking for what type of monsters my characters will come across based on what lives in certain areas, not what "type" of monster something is (which is oddly the default option).

When we go to the Game Rules>Monsters page can we get a nice little row of environment icons/pictures to click on that auto-filters to results of that environment, just like the row of icons by type?

There's already an environment filter in the monster search, which is under advanced filters. For example, here's a link to all monsters found in Arctic environments https://www.dndbeyond.com/monsters?filter-type=0&filter-search=&filter-cr-min=&filter-cr-max=&filter-environment=1&filter-armor-class-min=&filter-armor-class-max=&filter-average-hp-min=&filter-average-hp-max=&filter-is-legendary=&filter-is-mythic=&filter-has-lair=

Yeah, I was saying "I know I can use filters" but I think environment type is actually far more useful than the default "type" icons they display when you go to that page. I'd rather have environment than type as the default. Essentially with the icons they chose "type" as the default display option, but that's just one of many filters right?

I've just created a OneNote page with links to searches by environment filter and only using sources I own.  Thanks for sharing.